The waveform of an optical signal transmitted in an optical transmission system degrades by ASE noise, non-linear characteristics of an optical fiber, etc., resulting in degradation of transmission quality. In such a case, the degraded waveform of the optical signal is recovered by an optical waveform shaping device for shaping the waveform an optical signal. Furthermore, an optical waveform shaping device is used in an observation device using a femtosecond laser etc., for example, as it is important to shape a laser waveform.
For example, JP-A 2001-42274 discloses an optical waveform shaping device with a spatial light modulator for phase modulation and a spatial phase modulator for intensity modulation. However, the optical waveform shaping device disclosed in the publication uses two modulators each having a grass substrate, which inevitably leads to the expansion of the diameter of a beam. Thus, there is a problem of low resolution.
Patent document 1: JP-A 2003-90926
Patent document 2: JP-A 2002-131710